Turn system testing into it's own gem and rename

Renames `Rails::SystemTestCase` to `ActionSystemTest` and moves it to a
gem under the Rails name.

We need to name the class `ActionSystemTestCase` because the gem expects
a module but tests themselves expect a class.

Adds MIT-LICENSE, CHANGELOG, and README for the future.

1 files changed, 47 insertions, 0 deletions

diff --git a/actionsystemtest/lib/action_system_test/test_helpers/screenshot_helper.rb b/actionsystemtest/lib/action_system_test/test_helpers/screenshot_helper.rb
new file mode 100644
index 0000000000..37336e976f
--- /dev/null
+++ b/actionsystemtest/lib/action_system_test/test_helpers/screenshot_helper.rb
@@ -0,0 +1,47 @@
+module ActionSystemTest
+  module TestHelpers
+    # Screenshot helper for system testing
+    module ScreenshotHelper
+      # Takes a screenshot of the current page in the browser if the system
+      # test driver supports screenshots and the test failed.
+      #
+      # Additionally +take_screenshot+ can be used within your tests at points
+      # you want to take a screenshot if the driver supports screenshots. The
+      # Rack Test driver does not support screenshots.
+      #
+      # You can check of the driver supports screenshots by running
+      #
+      #   ActionSystemTest.driver.supports_screenshots?
+      #   => true
+      def take_screenshot
+        puts "[Screenshot]: #{image_path}"
+        puts find_image
+      end
+
+      private
+        def supported?
+          ActionSystemTest.driver.supports_screenshots? && !passed?
+        end
+
+        def image_path
+          path = "tmp/screenshots/failures_#{method_name}.png"
+          page.save_screenshot(Rails.root.join(path))
+          path
+        end
+
+        def find_image
+          if ENV["CAPYBARA_INLINE_SCREENSHOT"] == "artifact"
+            "\e]1338;url=artifact://#{image_path}\a"
+          else
+            name = inline_base64(File.basename(image_path))
+            image = inline_base64(File.read(image_path))
+            "\e]1337;File=name=#{name};height=400px;inline=1:#{image}\a"
+          end
+        end
+
+        def inline_base64(path)
+          Base64.encode64(path).gsub("\n", "")
+        end
+    end
+  end
+end